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Bad Water Pressure - Open Loop Geo Thermal

Bought an old 50's hours 5 years ago with a fuel oil system and no AC. I was convinced into buying a open loop geo thermal system from the in-laws who have one that works great. Overall cost was in line with a new propane furnace plus AC installed. One downside - poor water pressure. The sytem pulls from our well that services our house. So we have little to NO water pressure when it is running. And it runs alot to keep the house up. Good news is our fuel oil back up kicks on at a 2 degree difference so the cold Michigan Winters we do use a tank of fuel oil to kee up. My question - how can I improve the system to operate more efficiently and reduce water usage. Here are the specs:
Baird Model # GSVS361-A
Pressure Tank: Vertical - 20 gallong
Well 180' depth of 220' well 4 1/2"
Well Pump 1/2 horse power

When the geo was set up it pulls 6 gpm. Can it be tuned down?
Would putting a larger well pressure tank or two in-line pressure tanks be a solution?
How about a larger well pump?
Or can I convert a open loop to a close loop - rough estimate on what that would cost?

By the model # I assume this is a 3 ton unit. You will need 6 GPM for heating in your area. In summer it could be reduced a little 4-4.5 GPM. A larger tank would help but the 1/2 HP pump may not do the job, that's where the well guy comes in.

Open loop systems are more efficient than closed loops. Unless you have water quality issues. If so, you don't want an open loop. I think your pump is too small for what you are in need of. Either way you need to contact a well service that has geo experience and have estimates of replacing the pump with a 1 horse or maybe 1-1/2h.p. They should also be able to estimate making it a closed loop system. You can then decide which way is best for you.

When the geo was set up it pulls 6 gpm. Can it be tuned down?
Mfg spec sheet says 5 gpm is ok, but I'd stay with the 6 gpm

Would putting a larger well pressure tank or two in-line pressure tanks be a solution?
Probably not, sounds like you well may not be able to supply 6 GPM+ and you are actually getting < 6 gpm due to either too small of a pump for your depth of water (water depth, not well depth, likely you are drawing down quite a bit at 6gpm, hence the reduced pressure - I'd guess for household use the water in you well may come up to above 100 ft down - when you try to pump 6 gpm, the water level drops to 200 ft or more and your pump cannot handle that head at 6 gpm).
Do you have the pumping report from when the well was drilled? If not, you either need to read up on wells (a lot) or get your well guy in on the act.

How about a larger well pump?
Probably, my guess would be 'fer sure'. Say 200 ft depth plus say 30 psi for the house and 10 psi pipe drop = equivalent total head of almost 220 feet. 6 gpm is roughly 50 pounds per minute, say a pound a second = 250 or so ft-# second, pump efficiency typically is 60-70%, so that equates to needing more than 1/2 HP.

Or can I convert a open loop to a close loop -
Only if you drill a few more wells (see the jonjig thread for that)- rough estimate on what that would cost? , no pricing as previously stated.

Just getting back around to addressing this so I figured I owed everyone an answer as to what happened. My Geo started to shut down this February. We realized it because the system would be running and have perfect water pressure. I checked and water was flowing through the entire system and getting stopped on the "out" water at the pressure control valve and was not passing through. Called my Geo guy who is kind of a "under the table" operator. First time out he checked out the problem. Second time out he cleaned the system and replaced the valve (within ten minutes of him leaving I knew it wasn't fixed. Third time out he said my well wasn't producing enough water - shutting down the system and I needed to call the well guy.
Quoted 5 different well guys. My well record says I have a well from 1986 that produced 20-30 gallons per minute with the original 3/4 pump still in it. After alot of thought I decided to go with a new 1 1/2 HP penitek constant pressure system! Should get out for about $2350 and have enough watter for my entire house.... or so I thought.

It is done now and the well guy was great - it took him two days, new wire, new drop pipe, an acid job and he says it produces 10 gallons/minute. Well is capped to prevent draw down. I had Geo running with shower and washing machine which is the first time in 5 years! Yaah. Only two problems - (1) I'm about $4,000 in now with extra well work, equipment, geo-guy bill and extra fuel oil; but worst of all (2) Geo doesn't work - which leads me to believe that wasn't the original problem. He is supposed to come back out to check it out but any ideas what could be shutting down the water control valve? Electrical? Thermistat? Scale/Buildup (it is a new valve)?

Your having the well capped to prevent drawdown???
Not the best of ideas. that also prevents the well from recovering too. A well that produces just 10 gpm is not enough water to run a geothermal system, and supply a house too.
Your 1.5hp is going to easily over power your well and pump it empty.
This could also caue the heat pump to shut down from no flow.

Bergy - I agree. This is the last time I use him. The "clincher" to the entire story is our Geo guy made it back out and in his words "the system tricked him". All along it was the air filter/coil system, dirty and clogged causing the system to freeze and shut down..........So I didn't even HAVE to address my well issues now. But eventually would have.

CallaDrilling - Can you expand? I used a very reputable Well guy and he was great. He said that I was between a rock and a hard place and the well now with my new pump and system is the best option I have without drilling a new one. The Geo guy has the system set-up to to take 6 gallons per minutes and I now can do normal household activities (shower, dishwasher, sink) and still have decent water pressure. The capping was because we were drawing air and though we are only about 4 days in - it is working.

One more question> The Geo guy was here, system is working great. Maintaining a nice 70 degrees and my backup system hasn't kicked on. I even have more airflow at the vents. WAter pressure decent. My question that I still am confused on. The water out pipe has a house faucet, pressure control valve, house faucet. Between the Geo and the pressure control valve I get more than 6 gpm. Between the pressure control valve and the next faucet it seems more like 2 gpm. Is this right? Or is it still not using enough water?